• Title, Summary, Keyword: Magnesium

Search Result 2,609, Processing Time 0.049 seconds

A Study on the Greenhouse Gas Emission and Reduction Measures of Domestic Magnesium Production Process (국내 마그네슘 생산공정의 온실가스 배출량 산정 및 감축방안 연구)

  • Kim, Kyung-Nam;Im, Jin-Ah;Yoo, Kyung-Seun
    • Journal of Climate Change Research
    • /
    • v.5 no.3
    • /
    • pp.219-230
    • /
    • 2014
  • In this study, greenhouse gas emission of magnesium industry was estimated and the reduction potential of the greenhouse gas emission was evaluated with reduction technologies. Default value of IPCC guideline was used to calculate the greenhouse gas emission and $SF_6$ alternatives were considered in reduction potential. Import of magnesium ingot was 22,806 ton in 2013, which will be expected to increase to 81,700 ton with 20% rate in 2020. Magnesium ingot was consumed to produce magnesium alloy in diecasting process. Recently, commercial production of crown magnesium and magensium plate began. Based on ingot consumption, $CO_2$ emission of domestic magnesium industry was estimated to 504,000 ton, which is about 0.79% of domestic industrial emissions. Reduction potential of diecasting process was estimated to 489,320 ton by changing SF6 to alternative gases such as HFC-134a, Novec-612. Emission factor of Tier 3 level should be developed to enhance the accuracy of greeenhouse gas emission of magnesium industry.

Current Status on the Domestic Recycling of Magnesium (국내(國內) 마그네슘 리싸이클링 현황(現況))

  • Park, Hyung-Kyu;Kang, Min-Cheol
    • Resources Recycling
    • /
    • v.20 no.3
    • /
    • pp.3-11
    • /
    • 2011
  • Magnesium has been used as parts of vehicles, case materials of notebook PC and mobile phone, and its demand has been increasing recently. So until now, there has little magnesium scraps from the end of life vehicles or electronic parts, and most scraps has been generated from magnesium processing lines such as melting, die casting and machining. It is to review the present status of magnesium recycling. Here, domestic demand of magnesium, recycling amount and technologies used in domestic recycling companies were surveyed in recent years. In 2010, 8,840 tons of magnesium scraps were processed and used as raw materials for die casting products. The recycling ratio was estimated as 32.5%.

Superplasticity of Magnesium Alloys and SPF Applications (마그네슘합금의 초소성 특성과 응용)

  • Shim, Jae-Dong;Byun, Ji-Young
    • Korean Journal of Materials Research
    • /
    • v.27 no.1
    • /
    • pp.53-61
    • /
    • 2017
  • Magnesium alloys are of emerging interest in the automotive, aerospace and electronic industries due to their light weight, high specific strength, damping capacity, etc. However, practical applications are limited because magnesium alloys have poor formability at room temperature due to the lack of slip systems and the formation of basal texture, both of which characteristics are attributed to the hcp crystal structure. Fortunately, many magnesium alloys, even commercialized AZ or ZK series alloys, exhibit superplastic behavior and show very large tensile ductility, which means that these materials have potential application to superplastic forming (SPF) of magnesium alloy sheets. The SPF technique offers many advantages such as near net shaping, design flexibility, simple process and low die cost. Superplasticity occurs in materials having very small grain sizes of less than $10{\mu}m$ and these small grains in magnesium alloys can be achieved by thermomechanical treatment in conventional rolling or extrusion processes. Moreover, some coarse-grained magnesium alloys are reported to have superplasticity when grain refinement occurs through recrystallization during deformation in the initial stage. This report reviews the characteristics of superplastic magnesium alloys with high-strain rate and coarse grains. Finally, some examples of SPF application are suggested.

Useful Corrosion - Potential of Magnesium Alloys as Implants

  • Kaya, A. Arslan;Kaya, R. Alper;Witte, Frank;Duygulu, Ozgur
    • Corrosion Science and Technology
    • /
    • v.7 no.3
    • /
    • pp.162-167
    • /
    • 2008
  • Degradable implants have been in use for bone surgery for decades. However, degradable metal implants are one of the new research areas of biomaterials science. Magnesium has good biocompatibility due to its low toxicity, and it is a corroding, i.e. dissolvable, metal. Furthermore, magnesium is needed in human body, and naturally found in bone tissue. There have been some published reports also asserting the potential bone cell activation or bone healing effect of high magnesium ion concentrations. The classic method for achieving intertransverse process fusion involves autogenous iliac crest bone graft. Several investigations have been performed to enhance this type of autograft fusion. However, there is no research which has been undertaken to investigate the efficiency of pure magnesium particles in posterolateral spinal fusion. In this study, corrosion behavior of magnesium metal at the bone interface, the possibility of new bone cell formation and the degree of effectiveness in producing intertransverse process lumbar fusion in a sheep model have been investigated. Cortical bone screws were machined from magnesium alloy AZ31 extruded rod and implanted to hip-bones of sheep via surgery. Three months after surgery, the bone segments carrying these screws were removed from the sacrificed animals. Samples were sectioned to reveal Mg/bone interfaces and investigated using optical microscope, SEM-EDS and radiography. Optical and SEM images showed that there was a significant amount of corrosion on the magnesium screw. The elemental mapping results indicate, due to the presence of calcium and phosphorus elements, that there exists new bone formation at the interface. Furthermore, sixteen sheep were subjected to intertransverse process spinal fusions with pedicle screw fixation at various locations along their spines. Each animal was treated with 5cc autograft bone at one fusion level and 1cc magnesium+5cc autograft bone at the other. Six months after surgery, bone formation was evaluated by gross inspection and palpation, and radiological, histological, scanning electron microscopic and x-ray diffraction analyses. It may be stated that the potential for using useful corrosion of magnesium alloys in medical applications is expected to be significant.

EFFECT OF MAGNESIUM OXIDE CONTENTS ON THE PROPERTIES OF EXPERIMENTAL ALGINATES (산화마그네슘 함량이 실험적 알지네이트 인상재의 특성에 미치는 영향)

  • Bae Ill-Hwan;Woo Yi-Hyung;Choi Dae-Gyun
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.41 no.5
    • /
    • pp.551-564
    • /
    • 2003
  • Statement of problem : Magnesium oxide may increase pH of alginate, and supply magnesium ions to the polymerization reaction of alginate. Purpose : This study was designed to evaluate the influence of incorporation of magnesium oxide to alginate composition. Material and Method : Seven kinds of experimental alginates were prepared and used for the experiments. Components with unchanging concentrations were sodium alginate 15%, calcium sulfate 14%, sodium phosphate 2%, and zinc fluoride 3%. Contents of magnesium oxide were varied as 0%, 1%, 2%, 3%, 4%, 5%, 6%. Diatomaceous earth were added to each experimental groups as balance to be 100%. Control group was a MgO 0% group. Working time, setting time, elastic recovery strain in compression, compressive strength and tear resistance were measured were measured. Sample size for each groups were 10. Arithmetic means were used as each groups representative values. Regression test between MgO contents and results, Duncan's multiple range test, and One-way ANOVA test were done between groups at level of 0.05. Results : 1 Magnesium oxide made the working time and setting time as longer(p<0.0001). 2 Magnesium oxide did not alter the elastic recovery(p>0.05). 3. Magnesium oxide contents between 2% and 4% exhibited the lowest strain in compression on alginates(p<0.0001). 4. Magnesium oxide made the compressive strength and the tear resistance stronger(p<0.0001). Conclusion : These results mean that setting time of alginate maybe controlled and that mechanical properties maybe improved by the incorporation of magnesium oxide into alginate, without any reduction of elasticity.

Analysis of warm Deep Drawing of Magnesium Alloy Sheet (마그네슘 합금 판재의 온간 딥드로잉 해석)

  • Lee, M.H.;Kim, H.Y.;Kim, H.J.;Oh, S.I.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.294-297
    • /
    • 2007
  • Due to their low densities and high specific strength and stiffness, magnesium alloy sheets are very attractive lightweight materials for automotive and electrical products. However, the magnesium alloy sheets are usually formed at elevated temperature because of their poor formability at room temperature. To use of the magnesium alloy sheets for an industrial, their mechanical properties at elevated temperature and appropriate forming process conditions have to be developed. In this study, non-isothermal simulations of a square cup drawing from magnesium alloy sheets have been conducted to evaluate a proper forming process conditions such as the tool temperature, the tool shoulder radius, friction between the blank and the tools. According to this study, appropriate forming process conditions of square cup drawing at elevated temperature from magnesium alloy sheets are suggested.

  • PDF

The Present State and Task of Korea Magnesium Industry (한국마그네슘산업의 현황과 과제)

  • Kang, M.C.;Kim, H.S.;Cho, H.K.;Kim, K.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • /
    • pp.57-60
    • /
    • 2008
  • Magnesium alloys usage has been increased every year owing to its lightness, damping capacity, and EMI shielding, etc. In case of magnesium, it is mainly produced by diecasting due to high fluidity of melts. But, casting defect occurs many times because of low heat capacity of the magnesium. Therefore, wrought products can be applied for defect-free and mechanical properties. but it is insufficient in market share because of crystalline structure. The domestic market of wrought magnesium products are not revitalized compare to advanced countries. Accordingly we are going to forecast a domestic market of wrought products through searching the present of korean magnesium industry.

  • PDF

A Study of Technical Adapting on Injection Molding for Magnesium Alloy (마그네슘합금 사출성형의 기술적용에 관한 연구)

  • 강태호;김인관;최준영;김영수
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.833-836
    • /
    • 1997
  • Magnesium alloys are one of light weight material. Strength and stiffness of Magnesium alloys are enough to use for commercial product. Demand for strong, lightweight parts several computer and electronics have driven much of Magnesium injection molding's growth so far. And it is eighth most abundant resource on earth. In electronic device, electromagnetic interface and electrostatic discharge can affect performance. Magnesium injection molding is similar to normal plastic injection molding process. But some process condition is different. Especially injection speed and process temperature are so differs from other injection molding system. It just start for make something. But Magnesium injection molding is one of best alternate process for producing metal alloy part.

  • PDF

Influence of Magnesium and Calcium on the Serum Cholesterol Level Lowering (II) (마그네슘 및 칼슘이 혈청콜레스테롤 농도 저하에 미치는 영향(II))

  • Nam, Hyun-Keun
    • Journal of the Korean Applied Science and Technology
    • /
    • v.2 no.2
    • /
    • pp.21-24
    • /
    • 1985
  • The effects of dietary magnesium, calcium on the serum cholesterol concentration in rabbit was studied for a period of 21 days using isocalorids and isonitrogenous basal diet. It is investigated that the serum cholesterol level lowering by feeding with calcium, magnesium, sesame oil and perilla oil, did not appeared but perilla oil and magnesium feeding group appeared a little bit lowering. There was no effect for the total protein, but there was some sort of effect for albumin and globulin. Particulary, alpa-globulin was increased by calcium, magnesium, sesame oil and perilla oil feeding groups. The esterified cholesterol was increased at the magnesium and perilla oil diet group. It is also, investigate that there is almost no effect for the electrolytes concentration and transport phenomena in the cell through magnesium, calcium, sesame oil and perilla oil diet groups.

Studies on the Contents of the Trace Elements in Vegetables. (식품중 미량원소의 함량에 관한 연구)

  • Lee, S.K.;Youn, J.E.;Lee, S.H.;Hur, Y.H.;Lee, B.O.
    • Journal of Environmental Health Sciences
    • /
    • v.3 no.1
    • /
    • pp.13-16
    • /
    • 1976
  • Authors investigated the analyse trace elements in vegetables and Ginseng which indicated as follows: 1. Garlic, ginger, and onion has considerably large amounts of magnesium, garlic has in proper sequence as copper, aluminum, magnesium, bromine and mercury. Ginseng has in proper sequence as aluminum, magnesium, copper, bromine and mercury, and onion has in proper sequence as copper, manganese, aluminum, bromine and mercury. 2. Carrot has considerably large amounts of magnesium and has in proper sequence as copper, magnesium, aluminum, bromine and mercury. 3. Ginseng also has large amounts of magnesium and has in proper sequence as magnesium, aluminum, copper, bromine, and mercury.

  • PDF